The present invention relates to a bearing system for a first vehicle part, e.g., a driver""s cab of a truck, on a second vehicle part, e.g., a vehicle frame, the first vehicle part being movable from a first position relative to the second vehicle part into a second position.
Such a bearing system for a driver""s cab of a truck on a vehicle frame is described, for example, in European Published Patent Application No. 0 768 231. The bearing system is intended to reduce the operational lateral vibrations transferred from the vehicle frame to the driver""s cab and is intended to be effected in that the driver""s cab is able to be decoupled from the vehicle frame in terms of lateral vibrations in relation to the vehicle""s longitudinal axis. However, it is a disadvantage of this bearing system that it requires a relatively complex technical design.
It is an object of the present invention is to provide a bearing system that is easy and inexpensive to manufacture.
The above and other beneficial objects of the present invention are achieved by providing a bearing system that includes a shaft about which the first vehicle part is rotatable from the first position relative to the second vehicle part into the second position. The shaft is provided with a first flexible bearing element in a first shaft section and a second flexible bearing element in a second shaft section. The first vehicle part is supported on the shaft in the first shaft section via a first supporting element and in the second shaft section via the flexible second bearing element. The shaft is supported in its first shaft section on the second vehicle part via the first flexible bearing element and in its second shaft section via a second supporting element.
The foregoing arrangement according to the present invention provides a bearing system that is sturdy and inexpensive to manufacture and that may be arranged in the front section of the driver""s cab relative to the direction of travel, so that the driver""s cab may be raised or tilted about the shaft from the first position, i.e., the driving position, into the second position. The combination and arrangement according to the present invention of the supporting elements and of the flexible bearing elements, which may be designed, for example, as rubber bearings, makes it possible to reduce the transfer of vibrations to the driver""s cab.
According to an aspect of the present invention, a rotary spring is provided for generating a torsional force which acts between the first and the second vehicle parts, and which supports the movement of the first vehicle part from the first position into the second position. The torsional force is measured so that the driver""s cab is retained in its lower, first position due to its weight. The force required for moving the driver""s cab into the second position is reduced by the rotary spring.
A particularly inexpensive construction is achieved by configuring the shaft as a rotary spring.
The shaft may be configured as a torsion spring, e.g., as a straight torsion bar.
The shaft may perform the function of a rotary spring in a particularly simple manner in that a first end of the shaft is nonrotatably joined to the first supporting element, and in that the second end of the shaft is nonrotatably joined to the second supporting element.
The nonrotatable connection may by effected by positive locking. This may be achieved by configuring the first and/or the second end of the shaft as a spline shaft.
An adjusting device which twists the shaft relative to the first and/or second vehicle part(s) for adjusting the torsional force may be provided on the first and/or second end(s) of the shaft.
The shaft may extend through the first and/or through the second bearing element(s). In this manner, a particularly compact and stable construction is attained.
Moreover, the first and/or second bearing element(s) may include a sleeve bearing having an inner anchoring part and an outer anchoring part which is joined to the inner anchoring part via an elastic spring element, the inner anchoring part being supported on the shaft, and the outer anchoring part being supported on the first or second vehicle part. In this manner, it is possible to achieve a particularly effective vibration isolation of the driver""s cab.
The first and/or second bearing element(s) may be rotatably supported on the shaft via sliding bearings.
The vibration isolation of the driver""s cab may be further improved in that the first and/or second bearing element(s) is/are hydraulically damping elements. This may be achieved, for example, by hydraulically damped sleeve bearings having a working chamber filled with damping fluid and a compensating chamber which is separated from the working chamber and connected thereto via a passage, the volume of the working chamber being changed during a relative movement of the first and second supporting bodies, so that damping fluid is moved into the passage between compensating chamber and working chamber.
Moreover, the first and/or second supporting element(s) may be configured rigidly.
A bearing system which is particularly stable and inexpensive to manufacture is achieved in that the first and/or second supporting element(s) has/have two legs via which the supporting element is mounted on the shaft. In this context, the supporting elements may be made of a U-profile of steel in a particularly inexpensive manner.